This thesis is a work of historical sociology, presenting a developmental model of the British State that tracks its growth as a strategic system since 1066. It is comparable with the work of Mann (1986) and Tilly (1992) in arguing for a long-term model of state development that focusses on elite strategies. Boundary strategy is defined as a field of strategic action, with the state at its centre, which helps to produce a national population that imagines its internal boundaries of 'race', ethnicity, class and location in ways that conceal the objective structure of political and class relations. The thesis demonstrates how this field has developed in Britain over the centuries into six key strategies, defined as Blood, Pollution, Property, Civilisation, Nation and Race. The study achieves this by dividing British history since 1066 into four phases. The first is the Feudal State, 1066-1529. The second is the Protestant State, 1530-1829. The third is the Incorporation State, 1830 to the present day, and the fourth is the Fortress State, 1903 to the present day. It is argued that the Incorporation and Fortress phases of the state's development have unfolded concurrently since 1903, forming two distinct but interdependent functional dimensions. The thesis devotes one case study chapter to each phase. The final case study chapter then examines how the incorporation and fortress dimensions have been synthesised in the policy of asylum seeker dispersal since 1997. Each study is structured around the strategies and investigates how the strategies have responded to conflicts between elite interests and popular pressures 'from below'. The case studies also examine how popular violence against minorities has resulted from the unintended consequences of boundary strategies.